# NxReverse - Reverse Chronicle Order of Time Series

Returns the time-reversed order time series (i.e. the first observation is swapped with the last observation, etc.): both missing and non-missing values.

## Syntax

NxReverse(X)

X is the univariate time series data (a one dimensional array of cells (e.g. rows or columns)).

## Remarks

1. The time series is homogeneous or equally spaced.
2. The reverse operator changes the time-order from ascending to descending or vice versa:
$$\left[z_t\right] = \left[x_{T-t}\right]$$
Where:
• $\left[z_t\right]$ is the reversed time series.
• $\left[x_t\right]$ is the input time series.
• $T$ is the number of observations (including missing values) in the input time series.
3. The returned array has the same size as the input time series.